The Starliner spacecraft lost four thrusters while approaching the International Space Station last summer. NASA astronaut, Butch Wilmore took manual control, remembers Ars Technica, "But as Starliner's thrusters failed, Wilmore lost the ability to move the spacecraft in the direction he wanted to ...
But already, the failure of so many thrusters violated the mission’s flight rules. In such an instance, they were supposed to turn around and come back to Earth.
Were the thrusters essential to came back to Earth?
Were the thrusters essential to came back to Earth?
Some amount of them, yes